1. Field of the Invention
This invention relates to a color facsimile apparatus.
2. Related Background Art
Recently, color facsimile apparatuses have been proposed. For such color facsimile apparatuses, various types of printers are proposed.
Recently, an ink jet printer of bubble jet type has been proposed, which utilizes bubbles generated by thermal energy for discharging ink from nozzle toward a printing medium to print characters, images, etc. on the printing medium. In this printer, a heat-generating resistor (i.e., a heater) provided in each orifice is far smaller in size than the piezoelectric element used in the conventional ink jet printer. Thus, it permits high density multiplex arrangement of orifices to obtain high quality print image, as well as permitting high speed and low noise operation.
Meanwhile, the facsimile apparatus is required to be capable of not merely transmitting image at high speed but also receiving higher quality image at high speed. The bubble jet type ink jet printer as noted above is thought to be one of printers which can meet the above requirements.
However, in such color facsimile apparatus, if it is intended to full color print data received in a color receiving mode at all time, it is necessary to perform printing in;, for instance, four colors of yellow, magenta, cyan and black. Thus, the printing takes long time, and the received data can not be quickly confirmed.
Further, where printing is done in color at all times, a great quantity of ink is required.
Further, the above ink jet printer has the following problem.
The orifices of the recording head are subject to clogging caused by ink having viscosity increased due to non-use of the head, low relative humidity environment and difference in recording frequency or by attachment of dust. Accordingly, a discharge recovery mechanism is provided for removing ink of increased viscosity by causing forced discharging of increased viscosity ink from the inside of the orifices or withdrawing ink through a cap covering and protecting the head nozzle. In addition, when the recording head is out of use, its orifices are held covered by the cap to prevent non-discharge of ink.
However, even with the provision of the above measure, clogging of the ink nozzle is liable in such case as when the recording head has been out of use for long time or in a comparatively dry room because ink passages of ink nozzles are actually very narrow. Further, if some nozzles are used at a very low frequency during printing operation, they are liable to be clogged in the next printing.
Where such a printer is used for a facsimile apparatus, despite normal communication a white streaked or fringe-like pattern is generated in the output image to cause deterioration of image quality or missing information. To solve this problem, it may be thought to permit automatic monitoring of the state of the head before printing and refuse communication if the head is abnormal. However, if automatic reception is set for long time absence, the state of refusal of reception is inconveniently maintained for long time.
Particularly, in case of a color recording apparatus, three ink heads for respective colors of yellow, magenta and cyan are necessary, and therefore the probability of abnormal state of any one of the heads and probability of state of inability of reception are high.
The above problem is encountered not only in ink jet recording but also other recording systems where color image is reproduced for each color, for instance a thermal printer and electrophotographic system.
Meanwhile, in a bubble jet type ink jet printer for full color recording, recording heads for three different colors of Y, M and C or four different colors of Y, M, C and Bk are provided in a row or juxtaposed state such as to form images with relative movement of the ink heads and recording paper in the direction of the row.
For realizing a color facsimile apparatus, which can receive color image signal with such a color ink jet printer, it is important to permit high speed recording control.